Many seeds are a healthy alternative to snacking and will give you the crunch and flavour you're looking for.
Have you ever roasted seeds? Try roasting some pumpkin seeds this Halloween. Simply place cleaned seeds on a cookie sheet and bake in the oven at 350 until golden brown...you may wish you sprinkle seeds with some seasoning before roasting. Roasting also works well for other seeds too.
Some seeds like sunflower, sesame and flax are a great addition to salads or even by the handful. Be mindful of the flavoured sunflower seeds...read the label for sodium content and other values.
Pomegranate seeds are full of flavour and pack a juicy punch. (they make my cheeks tingle and I wish they were available more than once a year here..the juice however is good too if you can't wait for the seeds)
Cumin is a flavour punch in your sauces and for some meats as well.
Have you tried any of the seeds that are in the picture?
Picture found at Natural Cures Not Medicine